https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90055
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Andrew Pinski from comment #3) > (In reply to Martin Liška from comment #2) > > Fixed on trunk with r250959 which is: > > > > 364bc5b93b76cf88(08 Aug 2017 14:09): [took: 2.844s] result: OK > > sum: 0.0000 > > SVN revision: 250959 > > Author: amker > > * doc/invoke.texi: Document -ftree-loop-distribution for O3. > > * opts.c (default_options_table): Add OPT_ftree_loop_distribution. > > > > > > git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@250959 > > 138bc75d-0d04-0410-961f-82ee72b054a4 > > > > Using: > > gcc pr90055.c -O3 -ffast-math -march=haswell -mtune=haswell > > -fno-tree-loop-distribution > > > > it disappeared in r253934: > > > > Author: hubicka > > * x86-tune-costs.h (core_cost): Fix div, move and sqrt latencies. > > Those look like they are all would cause the issue to go latent. > > > > > and it started with r238033. > > This one does it might be the real cause of the issue. Nope, it just does less peeling for gaps.
